1. Field of the Invention
The present invention relates to an inserting instrument to which a rotary unit including a spiral tube is rotatably attached around a longitudinal axis. Further, it relates to a rotary unit to be attached to the inserting instrument, and an inserting apparatus including the inserting instrument and the rotary unit.
2. Description of the Related Art
In Jpn. Pat. Appln. KOKAI Publication No. 2011-520563, there is disclosed an endoscope that is an inserting instrument including an inserting section to which a rotary unit including a spiral tube is rotatably attached around a longitudinal axis. In this endoscope, the inserting section is inserted through the rotary unit. The inserting section includes an intermediate region covered with the rotary unit from an outer peripheral side, a far region (a distal region) disposed on a distal direction side with respect to the intermediate region, and a near region (a proximal region) disposed on a proximal direction side with respect to the intermediate region. The far region and the near region are not covered with the rotary unit. In the endoscope, the rotary unit rotates in a state where the spiral tube is pressed from a lumen wall toward an inner peripheral direction, whereby an impulsive force in a distal direction or an impulsive force in a proximal direction acts on the inserting section and the rotary unit.